274 research outputs found

    Self-Rated Mental Stress and Exercise Training Response in Healthy Subjects

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    Purpose: Individual responses to aerobic training vary from almost none to a 40% increase in aerobic fitness in healthy subjects. We hypothesized that the baseline self-rated mental stress may influence to the training response. Methods: The study population included 44 healthy sedentary subjects (22 women) and 14 controls. The laboratory controlled training period was 2 weeks, including five sessions a week at an intensity of 75% of the maximum heart rate for 40 min/session. Self-rated mental stress was assessed by inquiry prior to the training period from 1 (low psychological resources and a lot of stressors in my life) to 10 (high psychological resources and no stressors in my life), respectively. Results: Mean peak oxygen uptake (VO2peak) increased from 34 ± 7 to 37 ± 7 ml kg−1 min−1 in training group (p < 0.001) and did not change in control group (from 34 ± 7 to 34 ± 7 ml kg−1 min−1). Among the training group, the self-rated stress at the baseline condition correlated with the change in fitness after training intervention, e.g., with the change in maximal power (r = 0.45, p = 0.002, W/kg) and with the change in VO2peak (r = 0.32, p = 0.039, ml kg−1 min−1). The self-rated stress at the baseline correlated with the change in fitness in both female and male, e.g., r = 0.44, p = 0.039 and r = 0.43, p = 0.045 for ΔW/kg in female and male, respectively. Conclusion: As a novel finding the baseline self-rated mental stress is associated with the individual training response among healthy females and males after highly controlled aerobic training intervention. The changes in fitness were very low or absent in the subjects who experience their psychological resources low and a lot of stressors in their life at the beginning of aerobic training intervention

    Humans Use Predictive Gaze Strategies to Target Waypoints for Steering

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    A major unresolved question in understanding visually guided locomotion in humans is whether actions are driven solely by the immediately available optical information (model-free online control mechanisms), or whether internal models have a role in anticipating the future path. We designed two experiments to investigate this issue, measuring spontaneous gaze behaviour while steering, and predictive gaze behaviour when future path information was withheld. In Experiment 1 participants (N = 15) steered along a winding path with rich optic flow: gaze patterns were consistent with tracking waypoints on the future path 1–3 s ahead. In Experiment 2, participants (N = 12) followed a path presented only in the form of visual waypoints located on an otherwise featureless ground plane. New waypoints appeared periodically every 0.75 s and predictably 2 s ahead, except in 25% of the cases the waypoint at the expected location was not displayed. In these cases, there were always other visible waypoints for the participant to fixate, yet participants continued to make saccades to the empty, but predictable, waypoint locations (in line with internal models of the future path guiding gaze fixations). This would not be expected based upon existing model-free online steering control models, and strongly points to a need for models of steering control to include mechanisms for predictive gaze control that support anticipatory path following behaviours.A major unresolved question in understanding visually guided locomotion in humans is whether actions are driven solely by the immediately available optical information (model-free online control mechanisms), or whether internal models have a role in anticipating the future path. We designed two experiments to investigate this issue, measuring spontaneous gaze behaviour while steering, and predictive gaze behaviour when future path information was withheld. In Experiment 1 participants (N = 15) steered along a winding path with rich optic flow: gaze patterns were consistent with tracking waypoints on the future path 1–3 s ahead. In Experiment 2, participants (N = 12) followed a path presented only in the form of visual waypoints located on an otherwise featureless ground plane. New waypoints appeared periodically every 0.75 s and predictably 2 s ahead, except in 25% of the cases the waypoint at the expected location was not displayed. In these cases, there were always other visible waypoints for the participant to fixate, yet participants continued to make saccades to the empty, but predictable, waypoint locations (in line with internal models of the future path guiding gaze fixations). This would not be expected based upon existing model-free online steering control models, and strongly points to a need for models of steering control to include mechanisms for predictive gaze control that support anticipatory path following behaviours.Peer reviewe

    Characterization of Mixed Monolayers of Phosphatidylcholine and a Dicationic Gemini Surfactant SS-1 with a Langmuir Balance: Effects Of DNA

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    AbstractMonolayers of a cationic gemini surfactant, 2,3-dimethoxy-1,4-bis(N-hexadecyl-N;N-dimethyl-ammonium)butane dibromide (abbreviated as SS-1) and its mixtures with 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) were studied using a Langmuir balance. More specifically, we measured the force-area (π-A) curves and determined the elastic area compressibility modulus (Cs−1) as a function of lateral packing pressure and the mole fraction of the cationic lipid (XSS-1), with and without DNA in the subphase. Both SS-1 and POPC exhibited smooth compression isotherms, indicating their monolayers to be in the liquid expanded state. Even low contents (XSS-1<0.05) of SS-1 in a POPC monolayer condensed the film dramatically, up to 20% at 30mN/m. This effect is suggested to reflect reorientation of the P−-N+ dipole of the POPC headgroup. Accordingly, the magnitude of the condensing effect diminishes with XSS-1 and is not observed for mixed films of dioleoylglycerol and SS-1. Reorientation of the P−-N+ dipole is further supported by the pronounced increase in monolayer dipole potential ψ due to SS-1. The presence of DNA in the subphase affected the mixed POPC/SS-1 monolayers differently depending on the constituent lipid stoichiometry as well as on the DNA/SS-1 charge ratio. At a DNA concentration of 0.63μM (in base pairs) condensation of neat POPC monolayers was evident, and this effect remained up to XSS-1<0.5, corresponding to DNA/SS-1 charge ratio of 1.25. An expansion due to DNA, evident as an increase in ΔA/molecule, was observed at XSS-1>0.5. At a higher concentration of DNA (1.88μM base pairs) in the subphase corresponding to DNA/SS-1 charge ratio of 3.75 at XSS-1=0.5, condensation was observed at all values of XSS-1

    The automatic detection of heart failure using speech signals

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    Heart failure (HF) is a major global health concern and is increasing in prevalence. It affects the larynx and breathing - thereby the quality of speech. In this article, we propose an approach for the automatic detection of people with HF using the speech signal. The proposed method explores mel-frequency cepstral coefficient (MFCC) features, glottal features, and their combination to distinguish HF from healthy speech. The glottal features were extracted from the voice source signal estimated using glottal inverse filtering. Four machine learning algorithms, namely, support vector machine, Extra Tree, AdaBoost, and feed-forward neural network (FFNN), were trained separately for individual features and their combination. It was observed that the MFCC features yielded higher classification accuracies compared to glottal features. Furthermore, the complementary nature of glottal features was investigated by combining these features with the MFCC features. Our results show that the FFNN classifier trained using a reduced set of glottal + MFCC features achieved the best overall performance in both speaker-dependent and speaker-independent scenarios. (C) 2021 The Author(s). Published by Elsevier Ltd.Peer reviewe

    ANALISIS DAMPAK INDUSTRI 4.0 TERHADAP SISTEM PENGAWASAN KETENAGANUKLIRAN DI INDONESIA

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    ANALISIS DAMPAK INDUSTRI 4.0 TERHADAP SISTEM PENGAWASAN KETENAGANUKLIRAN DI INDONESIA. Telah dilakukan suatu kajian mengenai pengaruh gelombang Industri 4.0 terhadap sistem pengawasan ketenaganukliran di Indonesia. Industri 4.0 adalah istilah yang diterapkan pada berbagai transformasi yang demikian cepat dalam desain, manufaktur, operasi, serta layanan produk dan sistem produksi. Penggunaan 4.0 menandakan bahwa ini adalah revolusi industri keempat di dunia, meneruskan tiga lompatan besar sebelumnya, yatu: Manufaktur mesin uap dan air, produksi massal bertenaga listrik berbasis pembagian kerja, dan zaman elektronika dan teknologi informasi dengan otomatisasi tugas-tugas rumit. Berbagai penelitian menyebutkan bahwa Industri 4.0 mengubah banyak hal, termasuk: meningkatnya fleksibilitas produksi, kustomisasi massal, produktivitas, mutu produk, keterlibatan pelanggan dalam proses desain, semakin mendekatnya lokasi produksi ke pelanggan, dan model bisnis. Semua perkembangan ini tentunya harus diantisipasi oleh Badan Pengawas. Dengan demikian, tujuan dari kajian ini adalah untuk mengevaluasi hal-hal yang sudah atau perlu dilakukan oleh BAPETEN dalam rangka menyongsong era Industri 4.0. Kajian dilakukan dengan metode deskriptif, analitik dan kualitatif yang dilengkapi dengan studi literatur dan pengamatan praktik-praktik yang ada di BAPETEN. Kajian ini menyimpulkan bahwa BAPETEN sebagian telah melakukan antisipasi akan datangnya era Industri 4.0, namun masih ada banyak peluang untuk peningkatan
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